Hydrothermal syntheses of zeolite N from kaolin

Abstract Zeolite N, an EDI type framework structure with ideal chemical formula K 12 Al 10 Si 10 O 40 Cl 2 ·5H 2 O, was produced from kaolin between 100 °C and 200 °C in a continuously stirred reactor using potassic and potassic + sodic liquors containing a range of anions. Reactions using liquors such as KOH, KOH + KX (where X = F, Cl, Br, I, NO 3 , NO 2 ), K 2 X (where X = CO 3 ), KOH + NaCl or NaOH + KCl were complete (> 95% product) in less than 2 h depending on the batch composition and temperature of reaction. With KOH and KCl in the reaction mixture and H 2 O/Al 2 O 3  ~ 49, zeolite N was formed over a range of concentrations (1 M